Research for developing organic electronic devices is rapidly increasing worldwide as the organic electronic devices have the potential to radically change several aspects of everyday life. Further, the development and encapsulation of the organic electronic devices by low-cost fabrication allows implementation in numerous application areas, such as display screens, lighting, photovoltaics, radio-frequency identification (RFID) and chemical sensors, as well as to new-generation advanced applications.
Typically, such organic electronic devices convert electrical energy into radiation, followed by the detection of signals through various electronic processes. Finally, the radiation is converted back into electrical energy. Some examples of such electronic devices may include, but are not limited to, an organic thin-film transistor (OTFT), organic light-emitting diode (OLED), and organic photodiode (OPD).
Various techniques are utilized for fabrication of the organic electronic devices on substrates to improve their performance parameters, such as efficiency and power gain. A patterning step may be required for the fabrication of such organic electronic devices on the substrates. The process of fabrication and patterning may be carried out by various solution-processing techniques, such as spin-coating and ink-jetting.
Generally, a protective layer may be formed over a single substrate on which multiple organic electronic devices are pre-fabricated. However, in certain scenarios, it may be required to remove the protective layer from a discrete area of the substrate for the fabrication of additional organic electronic devices.
At present, the protective layer may be removed by using dry etching, such as plasma etching or reactive ion etching. However, usage of dry etching may result in the protective layer being either completely or partially removed. In some instances, the technique of dry etching may involve the use of extra mask layers so that active organic layers of the pre-fabricated organic electronic devices may not be attacked. However, such a use of extra-masked layers may lead to an increase in additional lithographic steps and incur additional cost. Further, such techniques for the protective layer removal may have a detrimental knock-on impact on overall device performance.
U.S. Pat. No. 6,274,397B1 discloses the deposition of polymer film (Teflon) on a passivation layer over the circuit elements of a semiconductor package. This is followed by the removal of the said film by use of an organic solvent. The polymer film is removed by dipping the said film in acetone. The drawback of this technique is that it is non-selective, and so all the polymer film must be removed.
U.S. Pat. No. 5,888,309A discloses formation of a microelectronics layer of a material susceptible to sequential etching on a substrate employed within a microelectronics fabrication. The etching is carried out by fluorine containing plasma etch method.
Cho et al, J. Electronic Materials, 1994, 23(8), 827, has disclosed the successful patterning of Teflon by use of O2 or CF4/O2 plasmas. The article also disclosed that the etching of Teflon was not possible if wet chemicals are used.
Therefore, there is a need for an improved process for selective removal of the protective layer for the fabrication of organic electronic devices that can overcome the aforesaid limitations.
Further limitations and disadvantages of conventional and traditional approaches will become apparent to those skilled in the art, through the comparison of described systems with some aspects of the present disclosure, as set forth in the remainder of the present application and with reference to the drawings.